1 /* asoundlib.h 2 ** 3 ** Copyright 2011, The Android Open Source Project 4 ** 5 ** Redistribution and use in source and binary forms, with or without 6 ** modification, are permitted provided that the following conditions are met: 7 ** * Redistributions of source code must retain the above copyright 8 ** notice, this list of conditions and the following disclaimer. 9 ** * Redistributions in binary form must reproduce the above copyright 10 ** notice, this list of conditions and the following disclaimer in the 11 ** documentation and/or other materials provided with the distribution. 12 ** * Neither the name of The Android Open Source Project nor the names of 13 ** its contributors may be used to endorse or promote products derived 14 ** from this software without specific prior written permission. 15 ** 16 ** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND 17 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 ** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE 20 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 ** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23 ** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 26 ** DAMAGE. 27 */ 28 29 #ifndef ASOUNDLIB_H 30 #define ASOUNDLIB_H 31 32 #include <sys/time.h> 33 #include <stddef.h> 34 35 #if defined(__cplusplus) 36 extern "C" { 37 #endif 38 39 /* 40 * PCM API 41 */ 42 43 struct pcm; 44 45 #define PCM_OUT 0x00000000 46 #define PCM_IN 0x10000000 47 #define PCM_MMAP 0x00000001 48 #define PCM_NOIRQ 0x00000002 49 #define PCM_NORESTART 0x00000004 /* PCM_NORESTART - when set, calls to 50 * pcm_write for a playback stream will not 51 * attempt to restart the stream in the case 52 * of an underflow, but will return -EPIPE 53 * instead. After the first -EPIPE error, the 54 * stream is considered to be stopped, and a 55 * second call to pcm_write will attempt to 56 * restart the stream. 57 */ 58 59 /* PCM runtime states */ 60 #define PCM_STATE_OPEN 0 61 #define PCM_STATE_SETUP 1 62 #define PCM_STATE_PREPARED 2 63 #define PCM_STATE_RUNNING 3 64 #define PCM_STATE_XRUN 4 65 #define PCM_STATE_DRAINING 5 66 #define PCM_STATE_PAUSED 6 67 #define PCM_STATE_SUSPENDED 7 68 #define PCM_STATE_DISCONNECTED 8 69 70 /* Bit formats */ 71 enum pcm_format { 72 PCM_FORMAT_S16_LE = 0, 73 PCM_FORMAT_S32_LE, 74 PCM_FORMAT_S8, 75 PCM_FORMAT_S24_LE, 76 77 PCM_FORMAT_MAX, 78 }; 79 80 /* Configuration for a stream */ 81 struct pcm_config { 82 unsigned int channels; 83 unsigned int rate; 84 unsigned int period_size; 85 unsigned int period_count; 86 enum pcm_format format; 87 88 /* Values to use for the ALSA start, stop and silence thresholds. Setting 89 * any one of these values to 0 will cause the default tinyalsa values to be 90 * used instead. Tinyalsa defaults are as follows. 91 * 92 * start_threshold : period_count * period_size 93 * stop_threshold : period_count * period_size 94 * silence_threshold : 0 95 */ 96 unsigned int start_threshold; 97 unsigned int stop_threshold; 98 unsigned int silence_threshold; 99 100 /* Minimum number of frames available before pcm_mmap_write() will actually 101 * write into the kernel buffer. Only used if the stream is opened in mmap mode 102 * (pcm_open() called with PCM_MMAP flag set). Use 0 for default. 103 */ 104 int avail_min; 105 }; 106 107 /* PCM parameters */ 108 enum pcm_param 109 { 110 PCM_PARAM_SAMPLE_BITS, 111 PCM_PARAM_FRAME_BITS, 112 PCM_PARAM_CHANNELS, 113 PCM_PARAM_RATE, 114 PCM_PARAM_PERIOD_TIME, 115 PCM_PARAM_PERIOD_SIZE, 116 PCM_PARAM_PERIOD_BYTES, 117 PCM_PARAM_PERIODS, 118 PCM_PARAM_BUFFER_TIME, 119 PCM_PARAM_BUFFER_SIZE, 120 PCM_PARAM_BUFFER_BYTES, 121 PCM_PARAM_TICK_TIME, 122 }; 123 124 /* Mixer control types */ 125 enum mixer_ctl_type { 126 MIXER_CTL_TYPE_BOOL, 127 MIXER_CTL_TYPE_INT, 128 MIXER_CTL_TYPE_ENUM, 129 MIXER_CTL_TYPE_BYTE, 130 MIXER_CTL_TYPE_IEC958, 131 MIXER_CTL_TYPE_INT64, 132 MIXER_CTL_TYPE_UNKNOWN, 133 134 MIXER_CTL_TYPE_MAX, 135 }; 136 137 /* Open and close a stream */ 138 struct pcm *pcm_open(unsigned int card, unsigned int device, 139 unsigned int flags, struct pcm_config *config); 140 int pcm_close(struct pcm *pcm); 141 int pcm_is_ready(struct pcm *pcm); 142 143 /* Obtain the parameters for a PCM */ 144 struct pcm_params *pcm_params_get(unsigned int card, unsigned int device, 145 unsigned int flags); 146 void pcm_params_free(struct pcm_params *pcm_params); 147 unsigned int pcm_params_get_min(struct pcm_params *pcm_params, 148 enum pcm_param param); 149 unsigned int pcm_params_get_max(struct pcm_params *pcm_params, 150 enum pcm_param param); 151 152 /* Set and get config */ 153 int pcm_get_config(struct pcm *pcm, struct pcm_config *config); 154 int pcm_set_config(struct pcm *pcm, struct pcm_config *config); 155 156 /* Returns a human readable reason for the last error */ 157 const char *pcm_get_error(struct pcm *pcm); 158 159 /* Returns the buffer size (int frames) that should be used for pcm_write. */ 160 unsigned int pcm_get_buffer_size(struct pcm *pcm); 161 unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames); 162 unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes); 163 164 /* Returns the pcm latency in ms */ 165 unsigned int pcm_get_latency(struct pcm *pcm); 166 167 /* Returns available frames in pcm buffer and corresponding time stamp. 168 * For an input stream, frames available are frames ready for the 169 * application to read. 170 * For an output stream, frames available are the number of empty frames available 171 * for the application to write. 172 */ 173 int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, 174 struct timespec *tstamp); 175 176 /* Write data to the fifo. 177 * Will start playback on the first write or on a write that 178 * occurs after a fifo underrun. 179 */ 180 int pcm_write(struct pcm *pcm, const void *data, unsigned int count); 181 int pcm_read(struct pcm *pcm, void *data, unsigned int count); 182 183 /* 184 * mmap() support. 185 */ 186 int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count); 187 int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, 188 unsigned int *frames); 189 int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames); 190 191 /* Start and stop a PCM channel that doesn't transfer data */ 192 int pcm_start(struct pcm *pcm); 193 int pcm_stop(struct pcm *pcm); 194 195 /* Interrupt driven API */ 196 int pcm_wait(struct pcm *pcm, int timeout); 197 198 /* Change avail_min after the stream has been opened with no need to stop the stream. 199 * Only accepted if opened with PCM_MMAP and PCM_NOIRQ flags 200 */ 201 int pcm_set_avail_min(struct pcm *pcm, int avail_min); 202 203 /* 204 * MIXER API 205 */ 206 207 struct mixer; 208 struct mixer_ctl; 209 210 /* Open and close a mixer */ 211 struct mixer *mixer_open(unsigned int card); 212 void mixer_close(struct mixer *mixer); 213 214 /* Obtain mixer controls */ 215 unsigned int mixer_get_num_ctls(struct mixer *mixer); 216 struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id); 217 struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name); 218 219 /* Get info about mixer controls */ 220 const char *mixer_ctl_get_name(struct mixer_ctl *ctl); 221 enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl); 222 const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl); 223 unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl); 224 unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl); 225 const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl, 226 unsigned int enum_id); 227 228 /* Set and get mixer controls */ 229 int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id); 230 int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent); 231 232 int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id); 233 int mixer_ctl_get_bytes(struct mixer_ctl *ctl, void *data, size_t len); 234 int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value); 235 int mixer_ctl_set_bytes(struct mixer_ctl *ctl, const void *data, size_t len); 236 int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string); 237 238 /* Determe range of integer mixer controls */ 239 int mixer_ctl_get_range_min(struct mixer_ctl *ctl); 240 int mixer_ctl_get_range_max(struct mixer_ctl *ctl); 241 242 #if defined(__cplusplus) 243 } /* extern "C" */ 244 #endif 245 246 #endif 247
